#pragma once
#include <etcd/Client.hpp>
#include <etcd/KeepAlive.hpp>
#include <etcd/Response.hpp>
#include <etcd/Watcher.hpp>
#include <etcd/Value.hpp>
#include <functional>
#include "logger.hpp"

namespace hdp
{
    // 服务注册客户端类
    class Registry
    {
    public:
        using ptr = std::shared_ptr<Registry>;
        Registry(const std::string &host)
            : _client(std::make_shared<etcd::Client>(host)),
              _keep_alive(_client->leasekeepalive(3).get()),
              _lease_id(_keep_alive->Lease())
        {
        }
        ~Registry()
        {
            _keep_alive->Cancel();
        }

        bool registry(const std::string &key, const std::string &val)
        {
            etcd::Response resp = _client->put(key, val, _lease_id).get();
            if (resp.is_ok() == false)
            {
                LOG_ERROR("服务注册失败: {}", resp.error_message());
                return false;
            }
            return true;
        }

    private:
        std::shared_ptr<etcd::Client> _client;
        std::shared_ptr<etcd::KeepAlive> _keep_alive;
        int64_t _lease_id;
    };

    // 服务器发现客户端类
    class Discovery
    {
    public:
        using ptr = std::shared_ptr<Discovery>;
        using NotifyCallback = std::function<void(std::string, std::string)>;
        Discovery(const std::string &host,
                  const std::string &base_dir,
                  const NotifyCallback &put_cb,
                  const NotifyCallback &del_cb)
            : _client(std::make_shared<etcd::Client>(host)), _put_cb(put_cb), _del_cb(del_cb)
        {
            etcd::Response resp = _client->get(base_dir).get();
            if (resp.is_ok() == false)
            {
                LOG_ERROR("获取服务列表失败: {}", resp.error_message());
            }

            int size = resp.keys().size();
            for (int i = 0; i < size; i++)
            {
                if (put_cb)
                    put_cb(resp.key(i), resp.value(i).as_string());
                // if(put_cb) put_cb(resp.value(i).key(),resp.value(i).as_string());
            }

            // 进行事件监控,监控数据发生的改变并调用回调函数进行处理
            _watcher = std::make_shared<etcd::Watcher>(_client.get(), base_dir,
                                                       std::bind(&Discovery::callback, this, std::placeholders::_1), true);
        }

        ~Discovery()
        {
            _watcher->Cancel();
        }

        void callback(const etcd::Response &resp)
        {
            if (resp.is_ok() == false)
            {
                LOG_ERROR("收到一个错误的事件通知: {}", resp.error_message());
                return;
            }

            for (auto const &ev : resp.events())
            {
                if (ev.event_type() == etcd::Event::EventType::PUT)
                {
                    if (_put_cb)
                        _put_cb(ev.kv().key(), ev.kv().as_string());
                    LOG_DEBUG("新增服务:{}-{}", ev.kv().key(), ev.kv().as_string());
                }
                else if (ev.event_type() == etcd::Event::EventType::DELETE_)
                {
                    if (_del_cb)
                        _del_cb(ev.prev_kv().key(), ev.prev_kv().as_string());
                    LOG_DEBUG("下线服务:{}-{}", ev.prev_kv().key(), ev.prev_kv().as_string());
                }
            }
        }

    private:
        NotifyCallback _put_cb;
        NotifyCallback _del_cb;
        std::shared_ptr<etcd::Client> _client;
        std::shared_ptr<etcd::Watcher> _watcher;
    };
}